1. Field of the Invention
The invention relates to a steering system for a material handling vehicle or the like.
2. Description of the Related Art
In a material handling vehicle such as a forklift, a lifting operation lever for a material handling device is located on the right side of an operator seated on a cab seat and a steering wheel (steering member) is located on the left side of the operator seated on the cab seat. Therefore, the operator operates the lifting operation lever with his/her right hand while operating the steering wheel with his/her left hand. A knob (operating portion) for operating the steering wheel is turnably attached to the steering wheel, and the operator grips the knob with his/her hand to turn the steering wheel. In order to load a cargo on forks, it is necessary to make fine adjustment of the forks in the right-left direction. As described in Japanese Patent Application Publication No. 2012-1092 (JP 2012-1092 A), Japanese Patent Application Publication No. 2009-288872 (JP 2009-288872 A), Japanese Patent Application Publication No. 2008-213769 (JP 2008-213769 A), and Japanese Patent Application Publication No. 5-92769 (JP 5-92769 A), fine adjustment of the forks in the right-left direction is made by operating the knob to finely steer a vehicle body.
In the forklift according to the related art, the knob may be located at a position at which the operator has difficulty in operating the knob depending on the operated state (turning angle) of the steering wheel. In this case, because it is difficult to operate the steering wheel as intended by the operator with the use of the knob, it is difficult to make fine adjustment of the forks in the right-left direction through fine steering of the vehicle body. FIG. 10A illustrates the neutral position of a steering wheel 200. For example, when the turning angle of the steering wheel 200 is a turning angle at which a knob 201 is located on the right side of the center of the steering wheel 200 as viewed from the operator as illustrated in FIG. 10B, it is difficult to operate the steering wheel 200 as intended by the operator with the use of the knob 201. Therefore, in this case, it is difficult to finely adjust the orientation of the forks, that is, the orientation of the vehicle body.